#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>
int removeElement(int* nums, int numsSize, int val)
{
    int N = numsSize;
    int src = 0, dest = 0;
    while (src < N)
    {
        if (nums[src] != val)
        {
            nums[dest] = nums[src];
            dest++;
            src++;
        }
        else
        {
            src++;
        }
    }
    return dest;
}
int main()
{
	int nums[] = { 1,2,1,2,3,4,5,6,3,4,5,6 };
	int val = 0;
	scanf("%d", val);
	int dest=removeElement(nums, sizeof(nums), val);
	return 0;
}